Shelter



FIG. 1 is a perspective view of a shelter showing my new design;

FIG. 2 is a side elevational view thereof, the other side being substantially identical;

FIG. 3 is a front elevational view thereof;

FIG. 4 is a top plan view thereof; and

FIG. 5 is a rear elevational view thereof. 

The ornamental design for a shelter, substantially as shown and described. 